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A Wearable Dual-Band Dielectric Patch Antenna for LTE and WLAN

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Journal of Electromagnetic Analysis and Applications 2012年第7期4卷 305-309页

作者： Mohamed Ali Soliman taha elsayedtaha Wael elsayed Swelam Ali MohamedGomaa Faculty of Electronic Engineering Menoufia University Menouf Egypt National Telecom Regulatory Authority Cairo Egypt RF/Microwave and Photonics Group Dep. of ECE University of WaterlooWaterloo Ontario Canada Shobraa Faculty of Engineering Benha University Cairo Egypt

In this paper, a dual-band microstrip patch array antenna for both the Multiple Input Multiple Output (MIMO) 4G Long-Term Evolution (LTE) and the Wireless Local Area Network (WLAN) systems is developed. Design simulation and optimization processes are carried out with the aid of the Advanced Design System (ADS) electromagnetic simula-tor that uses the full–wave Method of Moment (MoM) numerical technique [1]. Rectangular microstrip patch antenna constructed from Multi-Walled Carbon Nanotubes (MWCNT) ink with electrical conductivity of 2.2 × 104 S/m and relative permittivity of 5-j1 is used as the conductor patch [2]. The patch is deposited on Rogers substrate RT-Durid 5880 single substrate with (εr = 2.2) and thickness of 62 mil. U-shape slot is used to provide the dual-band. The pro-posed antenna operates at 3.5 GHz for LTE and 5 GHz for WLAN. The proposed antenna parameters are compared with published result of copper patch [3,4] for the same application. Great enhancement in antenna size, matching, and frequency band width are achieved for the proposed antenna at the expense of gain and antenna efficiency compared with copper one. The proposed MWCNT dielectric antenna size is 18.4 mm × 27 mm compared with size of 27 mm × 37 mm for copper one respectively. The gain is better than 7dBi with antenna efficiency of 87.29% at 3.5GHz for cop-per patch antenna and is better than 1.692 dBi with antenna efficiency of 27.05% at 3.5GHz for MWCNT respectively.

关键词： U-Slotted Patch Antenna MWCNT Dielectric Antenna and ADS

Utilization of Cement Kiln Dust (CKD) with Silica Fume (SF) as a Partial Replacement of Cement in Concrete Production

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Journal of Minerals and Materials Characterization and Engineering 2019年第4期7卷 137-149页

作者： Arafa elsayed Elhelloty Mohammed taha Nooman Rafik Khairy Abdelwahab Ahmed Islam Abdullah Civil Engineering Department Faculty of Engineering Al-Azhar University Cairo Egypt

This research aimed to clarify the role of by-product materials, such as CKD with SF as partial replacement by weight of cement in concrete manufacturing and inclusion on different characteristics of concrete. Concrete test specimens were mixed with 0%, 5%, 10%, 15%, 20% and 25% (CKD) with 15% (SF) as partial replacement by weight of Cement (CEM I-52.5N). Fresh concrete properties have been evaluated by workability measurement slump test. While hardened concrete properties have been evaluated by compressive, split tensile and flexural strengths tests at ages 7, 28 and 56 days, but evaluated for bond strength, modulus of elasticity and chemical composition measurement with X-Ray Fluorescence at age of 28 days. The test results have revealed that the increase of CKD amount with fixed amount of SF in concrete mixtures as partial replacement by weight of cement leads to gradual decrease of fresh concrete workability. In concrete mixtures, 20% CKD in the presence of 15% SF as partial replacement by the weight of cement are the optimum ratios which can be used without any negative effect on mechanical properties compressive, indirect tensile, flexural and bond strength at all the ages of concrete. Also modulus of elasticity and bond strength increased by 8.81% and 0.69% respectively at the age 28 days compared with control mixture.

关键词： Partial Replacement of Cement Cement Kiln Dust (CKD) Silica Fume (SF) Properties of Fresh and Hardened Concrete Modulus of Elasticity Bond Strength XRF

The Prognostic and Curative Benefits of Primary Tumor Resection versus No Resection in Stage IV Colorectal Cancer: A Comparative Study

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Surgical Science 2020年第3期11卷 39-49页

作者： Ibtsam Shehta Harera taha A. Baiomy Ahmed A. Obaya Shady E. Shaker Amr Samir Ahmed M. elsayed Enas Mahmoud Hamed Loay M. Gertallah Department of General Surgery Faculty of Medicine Zagazig University Zagazig Egypt Department of Clinical Oncology and Nuclear Medicine Faculty of Medicine Zagazig University Zagazig Egypt Department of Internal Medicine Faculty of Medicine Zagazig University Zagazig Egypt Department of Tropical Medicine Faculty of Medicine Zagazig University Zagazig Egypt Department of Radiology Faculty of Medicine Zagazig University Zagazig Egypt

Background: Colorectal cancer (CRC) who is initially diagnosed with single or multiple synchronous distant metastases has an incidence of about 20% of all CRC patients. There is a controversy regarding the role of resection of the primary tumors in those patients. The aim of this study was to explore the prognostic roles and survival advantages of surgical excision of the primary colonic tumor in patients with CRC who are primarily diagnosed with distant metastases. Patients and Methods: We included forty patients who were diagnosed initially with stage IV CRC. We have divided the included patients into two categories the first one included 20 patients that underwent surgical excision of the primary cancer followed by administration of chemotherapy and the remaining 20 patients were initially given chemotherapy without excision of the cancer. We followed patients for 24 months to detect progression, response to chemotherapy, recurrence free survival and overall survival rates. Results: There is statistically significant difference between patients underwent different initial management techniques regarding N stage of the tumor (p = 0.039), response to chemotherapy (p = 0.048), occurrence of relapse (p = 0.022), disease free survival (DFS) (p = 0.027) or overall survival (OS) rates (p = 0.001) (DFS and OS were significantly higher among patients who received initial surgical management. Primary surgical removal of the tumor improved OS rate by 8 months (p = 0.001). Conclusion: Surgical removal of the primary malignancy in mCRC patients before chemotherapy administration improves patients’ survival rates and response to chemotherapy that lead to a better prognosis.

关键词： Metastatic CRC (mCRC) Surgical Resection Chemotherapy Survival

Utilization of Cement Kiln Dust (CKD) with Silica Fume (SF) as a Partial Replacement of Cement in Concrete Production

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